\(|x+2005|^2 + |x+2007|^2 = 2\)
<=> \((x+2005 )^2+(x+2007)^2 =2 \)
<=> \((x^2 + 2.x.2005 + 2005^2) + ( x^2+2.x.2007 + 2007^2)\) = 2
<=> \(x^2+4010x+4020025+x^2 +4014x+4028049\) = 2
<=> \(2x^2 + 8024x= -8048072\)
<=> \(2x( x+4012) = - 8048072\)
<=> \(\begin{cases} 2x=-8048072 \\ x+4012=-8048072 \end{cases} \) <=> \(\begin{cases} x=-4024036\\ x= -8052084 \end{cases}\)
Vậy \(x \in \) {\(-4024036 ; -8052084 \) }
p/s : chắc là sai r ToT